Radio Shack

RadioShack has dropped in-store pricing on the iPhone 5s and iPhone 5c to its lowest offer yet. With a two-year contract, the iPhone 5s can be purchased starting at $79.99, and the iPhone 5c at $29.99. The deal comes hot on the heels of its April iPhone 5s promotion offering $100 off.

Customers can take advantage of these promotional prices on 16 GB iPhone models with service on AT&T, Sprint or Verizon networks. Trade in a working iPhone 4S and RadioShack will hand over a brand new iPhone 5s for free. Participants in the company's Trade & Save program can also get the iPhone 5c for no charge.

Anyone who has postponed buying an iPhone 5s now has a sweet deal to consider from RadioShack. Starting on Friday, stores will offer Apple's latest iPhone with 16GB of storage for just $99.99. Of course, in order to qualify for this subsidized sale price a two-year service agreement must be initiated with a wireless carrier.

iPhone 5s buyers can choose between AT&T, Sprint or Verizon to take advantage of the deal. Not only is RadioShack offering 50 percent off, but anyone upgrading can trade in a used smartphone for instant store credit. Depending on the appraisal, owners of the 16GB iPhone 4s can get up to $100 and the 16GB iPhone 5 can be traded in for up to $175.

The iPhone 5c price war rages on. Hours after Best Buy announced it would offer the new handset for only $50, RadioShack announced the same deal. Both electronics retailers will give customers a $50 gift card when they buy a $99 iPhone 5c. However not to be outdone, Walmart just announced it would begin selling the 16GB model for only $45 throughout the holiday season.

This is a great opportunity to make a profit by selling your old iPhone while still upgrading to Apple's latest handset. Both Gazelle and Nextworth are accepting trade-ins for all used iPhone models in working condition. You can get up to $115 in cash for a used iPhone 4, and up to $320 for a used iPhone 5. This is much better than Best Buy and RadioShack's $50 gift card deals. It also allows you to have enough money to take advantage of Walmart's $45 sale, and still have enough left over to pay off your carrier's early termination fees if you're still under contract. You can compare trade-in values for all the iPhone models here.

If you are planning to buy an iPhone 5 from Virgin Mobile tomorrow, you may want to check RadioShack first. The Shack is extending its $50 trade-in deal to Virgin Mobile iPhones. This means you could potentially nab an off-contract iPhone 5 for only $450, instead of $500. Virgin Mobile will be selling the 16GB iPhone 5 for $549.99 online and in stores starting June 28th. The 32GB and 64GB models will only be available through VirginMobileUSA.com for $650 and $750, respectively. This includes Virgin's no contract $30/month unlimited plans.

RadioShack is also offering deals on the iPhone for AT&T, Sprint, and Verizon customers. A lot of The Shack's iPhone deals are in store only, and the Virgin Mobile deal also only applies to "eligible trade-ins". Also don't forget, a lot of other retailers are currently offering trade-in deals in anticipation of the next-generation iPhone. You may want to shop around, or wait until this fall before locking yourself into any new two-year contracts.

Here's a list of retail stores that will be selling the iPhone 4S on October 14. This is not a complete list, just some suggestions on other places you can go if you don't have an Apple Store near you. All Apple locations will be opening at 8 am local time on Friday, October 14, and will be offering a free Personal Setup service.

AT&T, Verizon and Sprint stores will also be carrying the iPhone 4S, but are not a great option. If you have to buy it directly from your carrier I would call ahead to make sure they plan to have a lot in stock.

The iPhone 4S is $199.99 for the 16GB model, $299.99 for the 32GB model and $399.99 for the 64GB model. All prices require a new or upgraded contract.